Blade-sharpening machine



Nov. 5, 1929.

A. A. KOHLMILLER BLADE SHARPENING MACHINE Filed March 19, 1925 5 Sheets-Sheet l Aorneys.

Nov. 5, 1929. A. A. KOHLMILLER BLADE SHARPENING MACHINE Filed March 19, 1925 I5 Sheets-Sheet lave/afar /frea! lfo/zZmJ/Zer.

Nv. 5, l 929. A. A. KOHLMILLER 1,734,524

BLADE SHARPENING MACHINE Filed Mrch 19, 1925 5 sheets-sheet 5 Q i Kfm@ 3, 3s if f/ Patented Nov. 5, 1929 UNITED STATES PATENT OFFICE BLADE-SHARPENING MACHINE Application ined March 19, 1925. serial No. 16,738.

The object of this invention is to improve t-he speed, cost and quality `of the sharpening of blades and particularly safety blades; and the invention consists of t-he improvements over the machine shown in the patent to' J. F. Fullen and F. WV. Cochrane, #1,197,619 patented September 12, 1916.

One feature of the invention consists in providing each roll with 'a grinding or sharpening helix in the nature of a helical or spirally disposed rib and having a flat peripheral face for grinding or abrading a blade, and arranging the rolls inpairs with the helices of '15 the two rolls 'of each pair meshing with or overlapping each other. This arrangement causes a compound frictional or grinding movement of the helices that is progressively imparted to the blades so that the blades may be stationary and the blades and blade holders need not be fed or longitudinally moved during the grinding operation of the rolls. This avoids the annoyance and expense and other troubles resulting from the. requirement of feeding the blade or blade holder through the machines of the prior art.

An important improvement in this Inachine is the construction, combination7 arrangementanfd adjustment of the different pairs of rolls so that they may do successive and progressive grinding or treatment of the blades. To that end the sharpening heliees on rthe rolls of one pair overlap each other more than the helices on the rolls of the previous pair. Hence the tangential angles of the pairs' of rolls of the series will be gradually greater and their grinding action will grind or finish gradually a smaller portion of the surface 0f the blades so that when finished all points in the edges will be in straight lines. Thus the grinding rolls overlap slightly and form a small tangential angle which enables the rolls to hollen7 grind the sides of the blade for a considerable width. The next pair of rolls overlap more so that the tangential angle is greater and they will grind the sides of the blade for only about half the width ground by the previous rolls. A thirdy pair of rolls overlap still more and the tangential angle is still greater so that they treat the sides of the blade near its edge for only a slight width. Thus the honing is limited to only about half the width of the grinding done by the grinding rolls, and the stopping rolls polish and finish only the surface near the edge of the blade.

Another feature of the invention consists in means herein set forth for adjusting the rolls of each pair with reference to each other, y and so that they will always be parallel and the adjustment of them will be uniform and sim ultaneous throughout their length. Along with this is the means for delicate adjustment or movement of the adjusting means.

Another feature of the invention consists in the means for adjusting the blade holder so as to hold the blades properly between and up to the sharpening helices on the rolls, and particularly in view of the .tact that the different pairs of rolls have their helices overlapping to different extents, which makes such vertical adjustment of the blade holder and blades important every time they are introduced between a new pair of rolls. This adjustment alsois such as to enable the rolls to properly operate on and sharpen blades having different bevels and different thickness.

Another feature of the invention consists in n eans for guiding the blade holder between each pair of rolls so as to hold it true and prevent injury to the rolls and the first two or three blades as the blade holder is being introduced between the rolls; and also providing on said guiding means indications or lines forindicating the proper elevation of the blade holder and blades forthe particular pair of rolls, in view of the different elevations of the blades required for the grinding, honing and stropping pairs of rolls.

Also another feat-ure consists in making the grinding rolls relatively short so as to prevent excessive grinding of the first few blades as 95 the blade holder enters between the rolls and leaves the same and to produce a uniformly ground edge on the different blades in the blade holder, and to enable the operator to grind yone or two particularly dull blades without excessive grinding of the other blades in the holder.

rllie full nature of this invention will be understood from the accompanying drawings and the following description and claims.

ln the drawings:

Fig. 1 is a plan View ot one Jorin ot my blade sharpening machine, parts being broken away.

Fig. 2 shows in the upper part a plan view and in the lower part a side elevation of a roll adjusting bar, the saine being broken away between the ends. Y

Fig. 3 is a side elevation ot the device, parts being broken away.

Fig. 4L is an end elevation of a pair ot' rolls and the means 'for mounting them and of the 'blade holder in place for treatment of the razor blades, parts being broken awav.

Fig. 5 is section through a part of the apparatus on the line 55 ot Fig. 4.

Fig. 6 is a fragment-al plan view of a pair of olls ot' modified form with meshing in- Fig. 8 is a horizontal section through a part otl the machine on the line 8 8 of Fig. l the upper part of said Ligure showing the mounting at one end oi'f a pair orD rolls and the lower part of the ligure showing the mounting ot a pair of rolls at the other end, and parts being` broken away.

Figs. 9, 10 and 11 are diagrams illustrating the serial position ot the three pairs of rolls shown herein.

Fig. 12 is a diagram or" the treatment ot the razor blade 'by the diiierent pairs of rolls, the razor blade being shown in end elevation and the lower part broken away, and the side surtace being indicated by dotted lines.

Fig. 13 is side view of the upper part of a razor blade, the remainder being brolren away, with a diagram illustrating the diiierent parts thereof treated by the different pairs o1 rolls.

11i is an end view of the means-tor mov ing and holding the adjusting bar shown in the lower part orP Fig. 2.

ln the form ot the invention illust-rated and explained herein, there is a table 10 on which the mechanism constituting this invention is built. ln the actual construction of this machine the means for driving the rolls, such as an electric motor, is mounted immediately under the table 10, although the same is not shown and belts, not shown, extend therefrom to the pulleys 11 on the rolls 12, 13 and 14 for driving the rolls.

T iree pairs of rolls are shown herein, the rolls 12 and 15 being sharpening rolls, the rolls 13 and 1G beine' honing rolls, and the rolls 1e and 17 being stropping rolls. rhe invention, however, is not limited to any particular number ot rolls, for as many pairs ot rolls may be included as desired. ln many machines we use tour or six pairs ot rolls. The driving rolls 12, 13 and 14 drive the driven rolls 15, 16 and 17 by means of gears 1r secured on the driving rolls and meshing with the gears 19 secured on the driven rolls, as shown.

rl`he pairs of rolls are mounted beside each other as shown in Fig. 1 for the purpose hereafter eXpl-ainec andthe mounting ot each pair ot' rolls will appear in Figs. 3, 4 and 8. For each pair ot rolls and at each end ot each pair ot rolls there is a bearing stand 2O secured on the table 10 as seen in Figs. 3 and l and having a bearing head 21 on the upper end for the end of a roll. And the saine bearing head has secured transversely in its upper portion the rod 22 which extends ior the itull lengt-h ot the machine and entire set or rolls. T he detailed construction of the bearing tor the roll is not shown, as there is nothing pej culiar about it. The rod 22 is held secured in the bearing 21 by a set screw 23. The bearing head 21 at its upper end has a threaded eX- tension 2d, as shown in Fig. 8. A hanger 25 fits snugly on the rod 22 and furnishes bearing for the companion roll as shown in Fi el. Hence this bearing hangar 25 and the roll vl 'ch it supports are laterally adjustable -ith etere-nce to the other bearing roll. rEhe bearhanger 25 is substantially pressed towards bearing head 21 by a spiral spring 26 surunding the rod 22 and at one end bearing 'ainst a washer 27. which lies against a nut that screws on a. threaded sleeve 29 secured on the rodr-22 by the pin 30, as shown in Fig. 8. An arm 35 extends down from the lower end of the hanger 25, at each side ot the ma-A chine, and a rod '36 extends transversely ot the machine and is secured in each pair ot arms 35 as shown in Figs. 3 and il tor bracing the pair ot hangers 25V Yfor each pair ot rolls.

lt is important for reasons hereafter X- plaincd that said adjustable roller be adjusted with relation to its companion roll. This may be done by the nut- 31 only or by the bar 32 only, but it is preferably done by both nut 31 and bar 32, as shown in Fig. 8. It the bar 32 were removed, the bearing hangar 35 would bear against the nut 31 under the pressure of the spring 26. Then by adjusting the position ot the nut 31 the space between the aries of each pair of rolls would be increased or diminished. This, however, would require a separate manipulation of the nut 31 at each side 0I" the machine and it' the nuts would notalways equally adjust the pressure between the rolls ot each pair, the grinding of the blades would not be uniform throughout their length.

In order to reduce this trouble the wedge bar 32 is introduced. The nuts 31 are then set permanently in the same relative position or to a vertical plane between the rolls that is central to the longitudinal axis of the blade holder support and the frequent adjustment Ure of the distance between the axes ofthe rolls o each pair is eEected by operating the bar 32 longitudinally, and since said bar extends kentirely through the machine, the adjustment at both sides of the machine isl necessarily uniform at all times. The bar 32fha's a wed-ge surface 33 at one end and a similar wedge surface 34 near the other end. Hence when the bar is in the position. shown in Fig. 8, the movable roll would be pushed and held tothe right by the widened portion of the bar, as shown, but if the bar were withdrawn, the springs 26 would force the roll 15 nearer to the yroll 12. By the combined use of the nuts 3l and bar 32 a greater range of adjustmentis possible. The bar 32 has a handle ll extending downward from one end thereof as shown in Fig. 2.

The adjusting bars 32 are held in adjusted position and are also moved into adjusted position to eilect a very line adjustment by set screw or micrometer screw 38 which screws through the upturned outer end of the bar as shown in Fig. 2 and has a pair of spaced collars 39 between which the downwardly turned end of a holding bar 4:0 extends and said bar 40 is secure on the bearing 25. A slight turn oi the screw 38 will cause a very slight adjustment of the bar 32. Since the adjusting bar 32`has inclined surfaces the longitudinal movement of the bar will cause a slighty lateral movement of the bearing on which the holder is secured, and to perymit such movement theholder 40 is provided with a widened slot where it y'engages the screw 38 as seen in Fig. 14. f

` The mounting, adjusting means and construction are repeated for each pair of rolls, but all of the rolls are mounted in connection with the rods 22, and said rods have horizontal openings 42 kthrough ythem for the passage of the setting bars 32`as shown inFig. 8.

The rolls 12 to 17 consist each of a'central portion in the nature of a spindle which has secured on it a sleeve 5() carrying a grinder in the iorm' oi a helix 51. The sleeves 50 are .secured in place by set screws 52. The helices vary in material accordingto the work to be done. The helices on rolls 12and 15, shown in Fig. 1, are for grinding,ithat' is, doing` the lirst rough grinding,iand the 'chief extent of grinding of the blades. Hence its helices are made of abrasive material ot suitable consistency. The helices on the middle pair of rolls shown in Fig. 1 are for doingr liner grinding or sharpening and may be' called honing rolls. The helices are made of leather impregnated with abrasive material. The third set of helices shown in Fig. 1 is for line grinding or sharpening and may be called Stropping helices. The helices are made of leather with or without ne abrasive material imbedded therein. The grinding and polishing material may be varied as desired as Well as the number of pairs ot rolls may be increased. One object of having a plurality of parallel pairs of rolls varying as suggested is, that they can vall be operated at the same time and'in the machine shown the blades in three blade holders may be simultaneously treated. The blades in one holder are being ground while the blades in the next holder are being honed and the blades in the next holder stropped. This contributes materially to the convenience of the operator and especially the speed and the production of work of 'this machine.

In the machine shown in Figs. 1 and 3 each roll as stated is provided ywith a helix 51 rhaving a contact surface that is continuous and a unit with the helices so constructed and arranged that they mesh when in use. They are arranged on a pair of rolls so that they will mesh as shown, that is the helix on one roll will project into the helix of the other roll and may therefore overlap each other. The pitch of the helix 51 is suilicient to progressively grind the blade equally, that is, each circumferential section of the helix will progressively engage the blade along its edge suilicient to reach beyond where the next circumferential section of the helix had begun. his makes the grinding action of the helix continuously progressive 'from end to end of the roll and the blade.

ln the modified form ot grinder shown in Figs. 6 and 7, in which inclined rings are employed, each circumferential ring 152 is spaced from and independent of the other circumferential section. In other words, they are separate rings placed on the spindle with spaces between them and are not a continuous helix as shown in Fig. 1. They are, rhowever, inclined relative to the axis ot the spindle, so that they operate substantially the same as the spiral form of ring.

The object of these two forms ot sharpening rings is to distribute the grinding action ot the blade and prevent notches being ground inthe blade, as would be the case if the rings were truly circular so that the entire surface et the ring would always grind the same spot on the blade. If the circular ring were l@ ot an inch wide, each ring would grind a notch. on the blade 1A of an inch wide; but if the rings are inclined as shown herein, one circumferential section would grind a strip three or f times as wide on the blade as would a ci lar ring and the adjacent circumferential seci tions of the ring would overlap each others field of grinding, so that the grinding would be 'progressive along the edge of the blade from end to end and uniform.

` Under each pair of rolls, as seen in F ig. el, there is mounted a blade helder against which a number of razor blades 51 are clamped by the clamp 52. The details of the construction of this blade holder constitutes no necessary part of this invention, so :tar as the mounting ofthe blades in the blade holder is concerned. The blade holder extends entirely across the machine and has at its outer end a handle 53. It also has a rod-like back 54 secured to the lower edge of the blade holder 50 for strengthening same and giving it a self aligning swivel motion in the tubular support.

The blade holder is inserted in the machine by placing the back rod 54 in a tube 55 that is slotted at the top and in which the blade holder can be inserted longitudinally. The tube 55 is mounted in heads 56. The head 5G is secured on the upper end of a short rod 57 which extends down through a threaded sleeve 58 thatpasses through the table 10 and is secured thereon in adjustable position by the linger nut 59 and the tool nut G0. As seen in Fig. 8 there are three of these rods 57, one at each side and one in the middle of the machine. The rod 5f extends down below the sleeve 58 for some distance and has secured to its lower end a disk 61 by a screw 62 for supporting the spiral spring G3 which tends to hold the rod 57 down in its lowest position. But the rods 57 are pushed upward, and also the blade holders and blades by the adjusting rod 65 that extends through the machine entirely and through slot 66 in the sleeve 58 and rod 57. The adjusting bars 65 have a plurality of inclined surfaces 67, as seen in Figs. 3 and 5, in position to engage a rocking block 68 secured in the upper part of rod 57, as shown in Fig. 5. Vhen the blade holder is inserted in a machine, the bar 65 is moved to the left as shown in Fig. 3, whereby the blades are elevated to the grinding rings on the rolls for treatment. The bar 65, therefore, is enabled to vertically adjust the position of the blades to suit the particular pair of rolls with which it is being used. The importance of this will appear later. The bar 65 has on it a handle 70 as shown in Fig. 3. The adjusting bar 65 can be locked in adjusted position by the set screw 157, which screws through the rod 57 in contact with the bar 65. The screw extends through a vertical slot 158 in the threaded sleeve 58, as shown in Fig. 4. The blade adjusting bar 65 can be withdrawn by pressing upwardly the rod 57 against the action of the springs 63.

ln order to prevent the first blades in the holder from being` excessively or improperly ground, as they are being inserted between two rolls, a guide plate 71 is provided as shown in Fig. 4. This is a triangular plate with slots 72 for bolts 73 which extend through the slots into the bearing covers of the rolls at their axes. This permits lateral adjustment of the guide plate and permits the guide plate. to adapt itself to the lateral adjustment of the bearing hanger 25. The guide plate 71 has a vertical slot 74 in the lower edge and half way between the ends of the plate, as shown. This slot is wide enough to admit the blade holder but prevent any lateral movement thereof and it guides the the blade holder and blades for the diiferent pairs of rolls in the machine. hus the upper line 100 would indicate the position of the upper edge of the blades between the pair of rolls for grinding; the line 101 indicates the position of the upper edge of the blades between the rolls for honing, while the line 102 indicates the position of the upper edge of the blades between the rolls for stropping, as shown in Fig. 4.

The operation of the machine will now be explained. The rolls are adjusted with reference to each other, preferably as shown in Figs. 9 to 11. There it is shown in Fig. 9 that the helices of the rolls very slightly overlap each other tangentially. This leaves a sharp enclosed tangential angle between the rolls, as indicated by the lines and, therefore, permits the blade 51, shown in Fig. 12, to extend relatively far up towards the line which bisects the two rolls. This causes a wide grinding on each side of the blade, as indicated by the line 81 in Fig. 12, so that a wide surface or long concave bevel is ground on each side of the blade, as indicated by the brace between the two dotted lines 82 and 83, connected by the brace S4 in Fig. 13. This is the irst and the major grinding action of the machine on the blade and as seen in Fig. 12, it hollow grinds the blade far down. In the rough grinding operation, the grinding rolls 12 and 15 are relatively short, as seenin Figs. 1 and 3, and in operation the blade holder is moved back and forth while the rolls operate. These are abrasive grinders and are made short to prevent overhoning or sharpening of the blades.

After the blades have been treated for a few seconds in the lirst set of rolls, the blade holder is removed and inserted between the second pair of rolls, as shown in Fig. 10. These rolls are set so that their helices overlap each other more than those in Fig. 9 and, therefore, the tangential angle, as indicated by the lines 80, is greater than in Fig. 9. This set of rolls is used for honing the blades and, therefore, Vtheir action is confined more to the thin portion of the blade, as seen in Fig. 12, that is the action of the rolls in Fig. 10 extends down only to the line 85 and covers the surface indicated by the brace S6 in Fig. 18. This limitation of the surface honed avoids the honing of the lower part of the blade which was previously ground and, therefore, shortens the operation as well as sharpens the blade more.

After the blades have been honed, the holder is inserted in the third pair of rolls shown in Fig. ll where tliehelices overlap each other more than in the preceding set of rolls, as shown iii Figs. 9 and l0, and, therefore, the enclosed tangential angle is still greater than in F l() and the scope of treatment of the blade is still less. These lastrolls are used for stropping or finishing the sharpening treatmentl and these rolls operate only near the sharp edge of the blade for a slight width between the dotted line 82 and the line S7 indicated by the brace 88. rIhis final treatment gives a very smooth edge to the blade. As shown in Figs. 9, lO and ll, the razor blades or blade holder must be lowered with reference to the rolls, at each step in the operation, and this done by the cam bar G5, see Fig. 3. Therefore, the manner of mounting and vertically adjusting` the blade holder cooperates with the adjustment of the pair of rolls so as to effect the progressive treatment and sharpening of the blades as has been explained. The less the helices of the rolls overlap, the higher the blade must be adjusted and the overlapping adjustment of the helices of the rolls is e'llected by the operation of the cam bar 32 or the nuts 3l or both of these things. Also the helices on the rolls are so formed that they distribute their grinding action longitudinally of the blade so as to avoid the grinding of notches therein.

- Also the guide blade 7l prevents the blades from being injured or over-ground as the blade holder is being introduced. Furthermore only one roll of each pair in this inachine requires adjustment in order to vary the operation of the machine. f

Then a large number of pairs of rolls, say six, are employed in a machine, they `are grouped as desired for successive grinding, honing and stropping action, and are accordingly variously provided with different abrading surfaces and abrasives to accomplish such result.

In adjusting the bearings for the rolls, the nuts 8l are mainly used for the first parallel set-up or adjustment of the rolls and so adjust them that the adjusting bar 32 will be in its mean position so as to render the spreading or closing of the pair of rolls easily within the scope of the work to be done by the machine. l

It can be further stated that preferably the abrasive rings 51 and 52 which interlock in each pair of rolls do not touch each other so as to permit the free adjustment of the rolls.y They need not touch each other for causing al uniform grinding action ofthe blades, because they are inclined to such a degree that the scope of grinding action of the blade by each helix will overlap the action on the blade of the adjacent helices.

The invention claimed is:

l. A blade sharpening machine including a pairvof sharpening rolls, a rod near each of the'twoends of said rolls, a fixed bearing fon' each end of one of said rolls that is mounted oriy said rod, a bearing for each end of the other roll slidably mounted on said rod, a spring .for pressing each slidable 'bearing towards the fixed bearing, a threaded projec-` a table, a pair of bearing supports extending f upwardly therefrom, a rotary sharpening roll with its ends mounted in said bearing supports, a bearing rod extending through each of said bearing supports transversely of theroll and secured to the bearing supports, a companion rotary parallel adjacent sharpening roll, bearings slidable on said rod for the companion roll with downward extensiens, a rod connecting the extensions from' the slidable bearings at both ends of said' companion roll,and means for adjusting the slidable bearings with reference to the fixed bearings on said bearing rods, substantially assetfforth.

A blade sharpening machine including a pair of parallel rotary sharpening rolls with sharpening helices thereon adapted to mesh with and overlap each other, means for mounting said rolls so as to vary the overlapping of the helices thereon, a blade holder for holding the blades between the rolls, tubulau means for receiving and holding the lower edge of the blade holder, vertical rods for supporting said tubular means, springs for yleldingly supporting said rods, and nuts for applying tension to said springs and also for adjusting said tubular means to raise and lower said blade holder, for the purpose specified.y

4.. In a blade sharpening machine the combination of a support, a pairof parallel rotary sharpening rolls on said support, means for mounting said rolls adjacent to each other, a blade holder for holding the blades between the rolls, means for vertically adjusting said blade holder, a guide plate mounted at the ends of each pair of rolls for guiding the blade holder when inserted between the rolls, means for adjusting said guide plate transversely to said rolls and indicia on said guide plate for indicating the proper vertical adjustment of said blade holder and blades.

5. A blade sharpening machine including a iso table, a pair of rotary parallel adjacent sharp-` ening rolls mounted above the table and having sharpening rings thereon attached to in-A terlock with and overlap each other, means for mounting said rolls so as to vary the overlapping of the rings thereon, an externally threaded sleeve extending through said table under the points of contact of the rolls, nuts on said sleeve above and below the table for vertically adjusting the sleeve, rods extending through said sleeve having tube supporting heads on their upper ends, vertical slot-s in said rods below the heads thereon, a spring below the table for depressing each of said rods, an adjusting bar extending horizontally through the slots in said rods and supported by said sleeves and having inclined portions for vertically adjusting said rods and blade holder, and means tor locking said adjusting rod when adjusted.

6. A blade sharpening machine including a pair of rolls, sharpening Yhelices thereon that mesh or overlap, fixed bearings for mounting one roll, threaded extensions to said bearings, adjustable nuts on said eXtensions, slidable bearings for mounting the other roll to render it adjustable toward or from said nuts, parallel bearing rods for supporting said bearings and having horizontal slots through them, an adjusting wedge bar longitud inally movable through said slots and having wedge surfaces located between said nuts and sliding bearings, springs on said bearing rods for holding said sliding bearings in engagement with the wedge'surfaces of said bar, and means on one of the sliding bearings for holding said wedge bar in adjusted position.

ln witness whereof, I have hereunto aflixed my signature.

ALFRED A. KOHLMILLER. 

